. Elements of geology, or, The ancient changes of the earth and its inhabitants as illustrated by geological monuments. Geology. Ch. INCLINED STKATIFICATION. 47 Fir. 61. water to marine deposits, afterwards to be described. It will also appear, in the sequel, how much light the doctrine of a continued subsidence of land may throw on the manner in which a series of strata, formed in shallow water, may have accumulated to a great thickness. The exca- vation of valleys also, and other effects of denudation, of which I shall presently treat, can alone be understood when we duly appreciate the
. Elements of geology, or, The ancient changes of the earth and its inhabitants as illustrated by geological monuments. Geology. Ch. INCLINED STKATIFICATION. 47 Fir. 61. water to marine deposits, afterwards to be described. It will also appear, in the sequel, how much light the doctrine of a continued subsidence of land may throw on the manner in which a series of strata, formed in shallow water, may have accumulated to a great thickness. The exca- vation of valleys also, and other effects of denudation, of which I shall presently treat, can alone be understood when we duly appreciate the proofs, now on record, of the prolonged rising and sinking of land, throughout wide areas. To conclude this subject, I may remind the reader, that were we to embrace the doctrine which ascribes the elevated position of marine formations, and the depression of certain freshwater strata, to oscillations in the level of the waters instead of the land, we should be compelled to admit that the ocean has been sometimes everywhere much shallower than at present, and at others more than three miles deeper. Inclined stratification.—The most unequivocal evidence of a change in the original position of strata is afforded by their standing up perpen- dicularly on their edges, which is by no means a rare phenomenon, es- pecially in mountainous countries. Thus we find in Scotland, on the southern skirts of the Grampian's, beds of pudding-stone alternating with thin layers of fine sand, all placed vertically to the horizon. When Saussure first observed certain conglomer- ates in a similar position in the Swiss Alps, he remarked that the pebbles, being for the most part of an oval shape, had their longer axes parallel to the planes of strati- fication (see fig. 61). From this he in- ferred, that such strata must, at first, have been horizontal, each oval pebble having originally settled at the bottom of the water, with its flatter side parallel to the horizon, for the same reason that an egg
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